删除重复记录，保留一条

DELETE FROM 表名
WHERE ROWID IN (
SELECT rid
FROM (
SELECT
ROWID AS rid,
ROW_NUMBER() OVER (PARTITION BY bid ORDER BY create_time DESC) AS rn -- 按时间倒序
FROM 表名
) t
WHERE t.rn > 1 -- 保留时间最新的一条
);